cc: Devirtualize DisplayItem::ExternalMemoryUsage().

cc/playback/clip_path_display_item.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_PLAYBACK_CLIP_PATH_DISPLAY_ITEM_H_
 #define CC_PLAYBACK_CLIP_PATH_DISPLAY_ITEM_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 12 matching lines @@
  public:
   ClipPathDisplayItem(const SkPath& path, SkClipOp clip_op, bool antialias);
   explicit ClipPathDisplayItem(const proto::DisplayItem& proto);
   ~ClipPathDisplayItem() override;
 
   void ToProtobuf(proto::DisplayItem* proto) const override;
   void Raster(SkCanvas* canvas,
               SkPicture::AbortCallback* callback) const override;
   void AsValueInto(const gfx::Rect& visual_rect,
                    base::trace_event::TracedValue* array) const override;
-  size_t ExternalMemoryUsage() const override;
 
+  size_t ExternalMemoryUsage() const {
+    // The size of SkPath's external storage is not currently accounted for (and
+    // may well be shared anyway).
+    return 0;
+  }
   int ApproximateOpCount() const { return 1; }
 
  private:
   void SetNew(const SkPath& path, SkClipOp clip_op, bool antialias);
 
   SkPath clip_path_;
   SkClipOp clip_op_;
   bool antialias_;
 };
 
 class CC_EXPORT EndClipPathDisplayItem : public DisplayItem {
  public:
   EndClipPathDisplayItem();
   explicit EndClipPathDisplayItem(const proto::DisplayItem& proto);
   ~EndClipPathDisplayItem() override;
 
   static std::unique_ptr<EndClipPathDisplayItem> Create() {
     return base::MakeUnique<EndClipPathDisplayItem>();
   }
 
   void ToProtobuf(proto::DisplayItem* proto) const override;
   void Raster(SkCanvas* canvas,
               SkPicture::AbortCallback* callback) const override;
   void AsValueInto(const gfx::Rect& visual_rect,
                    base::trace_event::TracedValue* array) const override;
-  size_t ExternalMemoryUsage() const override;
 
   int ApproximateOpCount() const { return 0; }
 };
 
 }  // namespace cc
 
 #endif  // CC_PLAYBACK_CLIP_PATH_DISPLAY_ITEM_H_